This invention relates to the field of medical and surgical techniques and instruments, and more particularly to a method for the dilation of a puncture site in fascial tissue or a nephrostomy tract dilation.
In the current practice, puncture sites in the renal pelvis are dilated with tapered tubes of progressively larger sizes until the desired size is reached. The main difficulty with such an approach is the penetration of the ileo-lumbar fascia at the kidney. This fascia is a layer of strong fibrous tissue that is very difficult to dilate. As the tapered dilators enter such a layer, considerable axial force is required to penetrate. This force results in pain for the patient and the increased risk of damage to surrounding tissue. The present device does not use axial force to dilate tissue perpendicular to the puncture axis. Instead, the device consists of a modified long-nosed surgical clamp. The jaws of the clamp are hollowed out so that they can be inserted initially over a wire guide similar to a regular dilator. Once the tip ends of the clamp are through the fascia and into the renal pelvis, the clamp is opened by forcing the jaws to spread apart, thus tearing the fascial tissue and enlarging the puncture. The clamp is then closed, rotated 90% or so and then the process is repeated. This is continued until the opening to the fascial material is large enough to accept whatever device the physician plans to use next.
Many variations and types of surgical instruments have appeared and representative examples of these variations and types are disclosed by the following group of patent references. Each reference pertains in one way or another to surgical instruments, though some references are believed to be more relevant to the present invention than others.
______________________________________ Patent No. Patentee ______________________________________ 474,130 Henger 1,592,836 Moench 1,340,501 Roberts 762,743 McDade 3,446,211 Markham 4,034,746 Williams 4,449,532 Storz 1,097,978 Johnson ______________________________________
Henger discloses a surgical instrument designed to be taken apart and reunited in the simplest manner to allow for thorough cleaning and sharpening. Henger is relevant to the present invention only in that an instrument similar to that illustrated in FIGS. 1 through 5 may be modified to satisfy the present invention. Modification would be required because the instruments disclosed in Henger have no wire guide channel.
Moench discloses a surgical instrument for removal of small objects from the nasal, auricular or other cavities. FIGS. 1 and 3 disclose a rod or shank 10 which is made of wire and slides within a channel and tube 11. Shank 10 and tube 11 operate to grip a small object. The relevance of Moench is limited to the disclosure of an instrument in which a wire is slidably inserted in a channel. It should be noted that shank 10 is not a guide for tube 11, but instead tube 11 protects shank 10 to allow it to be inserted into a cavity. Also it is apparent from Moench that the instrument disclosed therein can't be opened for tearing of tissue.
Roberts discloses a surgical appliance adapted for tying knots in ligatures in cavities where it is difficult or impossible to reach with the hands. FIGS. 2 and 3 disclose grooves 11 in the non-adjacent sides of jaws 5. Grooves 11 extend longitudinally along jaws 5 but are inclined with respect to the axis of the jaw to provide an opening at the side of the jaw. The grooves 11 and openings are for insertion of ligatures therethrough. The relevance of Roberts is limited to the disclosure of an instrument with side-ports and grooves for holding tubular material. It should be noted that the grooves in Roberts are not in adjacent sides of the jaws to form a channel for receiving a wire guide and cross-sections of the jaws are not designed to accommodate tearing of tissue.
McDade discloses a cervical director for use with an applicator in introducing material into the uterus. FIGS. 1 and 2 disclose curved blades 3 and 3a which are hingedly attached to one another so that they may be forced apart when gauze is inserted therethrough. The relevance of McDade is limited to the disclosure of an instrument which has a channel for slidably receiving material. The McDade device clearly is not adopted for tearing tissue with the jaws when the handles of the instrument are moved apart as McDade discloses only a single handle and no pair of handles.
Markham discloses a surgical clamp. FIGS. 1 and 7 through 9 disclose a clamp with longitudinally extending recesses. The relevance of Markham is limited to the disclosure of an instrument with a longitudinally extending recesses. The device disclosed in Markham may be modified to satisfy the teachings of the present invention, but the device does not, as disclosed, teach the present invention.
Williams discloses a surgical retractor. The only relevance of the instrument disclosed in Williams is that it is designed to spread or increase the width across an incision.
Storz discloses a dilator to facilitate endoscope insertion into the body. FIG. 1 discloses a dilator with telescoping tubes 3 through 10 adapted to be slid along a wire 1. Storz is relevant only in that it discloses a device which when used in conjunction with a wire guide dilates the puncture site. The Storz disclosure is typical of the devices presently used for dilation of the renal tissue as previously described.
Johnson discloses a combined dilator and catheter. FIG. 6 discloses a surgical instrument with longitudinal channels or grooves 12 in the meeting of jaws 4 to form a longitudinal passage. Johnson also discloses notches in flow communication with longitudinal passes for discharge of secretion, however it is believed that the relevancy ends at that point. Johnson is substantially different in its disclosure as compared to the invention disclosed in this application because the invention disclosed in this application uses a wire guide to guide it to the site at which enlargement is accomplished. The Johnson device, on the other hand, is a combined dilator and catheter which is used to dilate and position a catheter in place.
Although the foregoing references disclose a variety of surgical instruments, it is to be noted that none reveal a surgical instrument with groves in the meeting faces of the jaws and side ports to allow for the instrument to be slidably engaged with a wire guide and inserted into a puncture in renal tissue and then through opening and closing of the handles to tear a hole of sufficient diameter in the tissue for insertion of other instruments. The method disclosed in this application is beneficial in that it helps to alleviate the discomfort to the patient and danger of damage to the surrounding tissue that plague other devices and methods for dilation of renal tissue.